DTC B1500: Fuel Sender Open Detected

DTC detecting condition: 

Open circuit in fuel gauge circuit

Trouble symptom: 

• Defective fuel gauge.
• Fuel level warning light blinks.

Wiring diagram: 

Fuel gauge system Ref. to WIRING SYSTEM>FUEL GAUGE SYSTEM>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK DTC. 

   Read the DTC of [Combination Meter] using the Subaru Select Monitor. Ref. to COMBINATION METER (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is DTC B1500 displayed? (Current malfunction)

   Yes  : Go to  2.

   No  : Go to  6.

2. CHECK COMBINATION METER. 
   1. Using the Subaru Select Monitor, check the following items in the [Active Test] of [Combination Meter]. Ref. to COMBINATION METER (DIAGNOSTICS)>ACTIVE TEST .
      • Fuel Meter Operation
      • Remaining fuel warning

   Is the operation of [Fuel Meter Operation] and [Remaining fuel warning] OK?

   Yes  : Go to  3.

   No  : Replace the combination meter. Ref. to INSTRUMENTATION/DRIVER INFO>COMBINATION METER .

3. CHECK HARNESS (OPEN CIRCUIT). 
   1. Turn the ignition switch to OFF.
   2. Disconnect the combination meter connector and the fuel level sensor connector and the fuel sub level sensor connector.
   3. Using the tester, measure the resistance between terminals.

      Connector and terminal 

      (i10) No. 25 - (R58) No. 1:

      (i10) No. 26 - (R59) No. 2:

      (R58) No. 4 - (R59) No. 1:

   Is the resistance 10 Ω or less?

   Yes  : Go to  4.

   No  : Repair the open circuit of harness or replace harness.

4. CHECK HARNESS (GROUND SHORT CIRCUIT). 

   Using the tester, measure the resistance between terminals.

   Connector and terminal 

   (i10) No. 25 - Chassis ground:

   (i10) No. 26 - Chassis ground:

   Is the resistance 10 Ω or less?

   Yes  : Repair the short circuit of harness or replace harness.

   No  : Go to  5.

5. CHECK FUEL LEVEL SENSOR. 

   Check the fuel sub level sensor as a single part. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL LEVEL SENSOR . Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL SUB LEVEL SENSOR .

   Is the check result OK?

   Yes  : Go to  6.

   No  : Replace the sensor. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL LEVEL SENSOR . Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FUEL SUB LEVEL SENSOR .

6. CHECK CONNECTOR. 
   1. Turn the ignition switch to OFF.
   2. Disconnect connectors.

   Is there poor contact of connector?

   Yes  : Repair or replace the poor contact of connector.

   No  : Go to  7.

7. CHECK DATA MONITOR. 

   Using the Subaru Select Monitor, check the following items in the [Data monitor] of [Combination Meter]. Ref. to COMBINATION METER (DIAGNOSTICS)>DATA MONITOR .

   • Fuel level resistance

   Does [Fuel level resistance] indicate 15 - 480 Ω?

   Yes  : Even if DTC is displayed, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

   NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

   No  : Replace the combination meter. Ref. to INSTRUMENTATION/DRIVER INFO>COMBINATION METER .